White roofs – an effective cooler for houses
Another option is not to whitewash roofs, but to green them with foliage. This is already being adopted in many cities
There is a third option competing for roof space to take the heat out of cities — covering them in photovoltaic cells. PV cells are dark, and so do not reflect much solar radiation into space. But that is because their business is to capture that energy and convert it into low-carbon electricity.
Solar panels “cool daytime temperatures in a way similar to increasing albedo via white roofs,” according to a study by scientists at the University of New South Wales. The research, published in the journal Scientific Reports last year, found that in a city like Sydney, Australia, a city-wide array of solar panels could reduce summer maximum temperatures by up to 1 degree C. …….
The lesson then is that light, reflective surfaces can have a dramatic impact in cooling the surrounding air – in cities, but in the countryside too. Whitewashed walls, arrays of photovoltaic cells, and stubble-filled fields can all provide local relief during the sweltering decades ahead.
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Urban Heat: Can White Roofs Help Cool World’s Warming Cities?
It has long been known that installing white roofs helps reduce heat buildup in cities. But new research indicates that making surfaces more light-reflecting can have a significant impact on lowering extreme temperatures – not just in cities, but in rural areas as well.Yale Environment 360 MARCH 7, 2018 Summers in the city can be extremely hot — several degrees hotter than in the surrounding countryside. But recent research indicates that it may not have to be that way. The systematic replacement of dark surfaces with white could lower heat wave maximum temperatures by 2 degrees Celsius or more. And with climate change and continued urbanization set to intensify “urban heat islands,” the case for such aggressive local geoengineering to maintain our cool grows.The meteorological phenomenon of the urban heat island has been well known since giant cities began to emerge in the 19th century. The materials that comprise most city buildings and roads reflect much less solar radiation – and absorb more – than the vegetation they have replaced. They radiate some of that energy in the form of heat into the surrounding air. The darker the surface, the more the heating. Fresh asphalt reflects only 4 percent of sunlight compared to as much as 25 percent for natural grassland and up to 90 percent for a white surface such as fresh snow. Most of the roughly 2 percent of the earth’s land surface covered in urban development suffers from some level of urban heating. New York City averages 1-3 degrees C warmer than the surrounding countryside, according to the U.S. Environmental Protection Agency – and as much as 12 degrees warmer during some evenings. The effect is so pervasive that some climate skeptics have seriously claimed that global warming is merely an illusion created by thousands of once-rural meteorological stations becoming surrounded by urban development. Climate change researchers adjust for such measurement bias, so that claim does not stand up. Nonetheless, the effect is real and pervasive. So, argues a recent study published in the journal Nature Geoscience, if dark heat-absorbing surfaces are warming our cities, why not negate the effect by installing white roofs and other light-colored surfaces to reflect back the sun’s rays? During summer heat waves, when the sun beats down from unclouded skies, the creation of lighter land surfaces “could help to lower extreme temperatures… by up to 2 or 3 degrees Celsius” in much of Europe, North America, and Asia, says Sonia Seneviratne, who studies land-climate dynamics at the Swiss Federal Institute of Technology (ETH) in Zurich, and is co-author of the new study. It could save lives, she argues, and the hotter it becomes, the stronger the effect. Seneviratne is not alone in making the case for boosting reflectivity. There are many small-scale initiatives in cities to make roof surfaces more reflective. New York, for instance, introduced rules on white roofs into its building codes as long ago as 2012. Volunteers have taken white paint to nearly 7 million square feet of tar roofs in the city, though that is still only about 1 percent of the potential roof area. Chicago is trying something similar, and last year Los Angeles began a program to paint asphalt road surfaces with light gray paint. Outside the United States, cool-roof initiatives in cities such as Melbourne, Australia are largely limited to encouraging owners to cool individual buildings for the benefit of their occupants, rather than trying to cool cities or neighborhoods. The evidence of such small-scale programs remains anecdotal. But now studies around the world are accumulating evidence that the benefits of turning those 1 percents into 100 percents could be transformative and could save many lives every year. Keith Oleson of the National Center for Atmospheric Research in Boulder, Colorado looked at what might happen if every roof in large cities around the world were painted white, raising their reflectivity — known to climate scientists as albedo — from a typical 32 percent today to 90 percent. He found that it would decrease the urban heat island effect by a third — enough to reduce the maximum daytime temperatures by an average of 0.6 degrees C, and more in hot sunny regions such as the Arabian Peninsula and Brazil. Other studies suggest even greater benefits in the U.S. In a 2014 paper, Matei Georgescu of Arizona State University found that “cool roofs” could cut temperatures by up to 1.5 degrees C in California and 1.8 degrees in cities such as Washington, D.C. But it may not just be urban areas that could benefit from a whitewashing. Seneviratne and her team proposed that farmers could cool rural areas, too, by altering farming methods. Different methods might work in different regions with different farming systems. And while the percentage changes in reflectivity that are possible might be less than in urban settings, if applied over large areas, she argues that they could have significant effects…….. Another option is not to whitewash roofs, but to green them with foliage. This is already being adopted in many cities. In 2016, San Francisco became the first American city to make green roofs compulsory on some new buildings. New York last year announced a $100-million program for cooling neighborhoods with trees. So which is better, a white roof or a “green” roof? Evidence here is fragmentary. But Georgescu found a bigger direct cooling effect from white roofs. Vincenzo Costanzo, now of the University of Reading in England, has reached a similar conclusion for Italian cities. But green roofs may have other benefits. A study in Adelaide, Australia, found that besides delivering cooling in summer, they also act as an insulating layer to keep buildings warmer in winter. There is a third option competing for roof space to take the heat out of cities — covering them in photovoltaic cells. PV cells are dark, and so do not reflect much solar radiation into space. But that is because their business is to capture that energy and convert it into low-carbon electricity. Solar panels “cool daytime temperatures in a way similar to increasing albedo via white roofs,” according to a study by scientists at the University of New South Wales. The research, published in the journal Scientific Reports last year, found that in a city like Sydney, Australia, a city-wide array of solar panels could reduce summer maximum temperatures by up to 1 degree C. ……. The lesson then is that light, reflective surfaces can have a dramatic impact in cooling the surrounding air – in cities, but in the countryside too. Whitewashed walls, arrays of photovoltaic cells, and stubble-filled fields can all provide local relief during the sweltering decades ahead. https://e360.yale.edu/features/urban-heat-can-white-roofs-help-cool-the-worlds-warming-cities |
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1.This month
For international nuclear news go to https://nuclear-news.net/
Ethics, Nuclear Power, and Global Heating – theme for December 2019
Ethics of Nuclear Energy Abu-Dayyeh (P.hD) Amman – H.K. of Jordan Ayoub101@hotmail.com E_case Society (President) www.energyjo.com [Extract]
“……2- Health Risk Analysis
If “risk” is defined as the product of probability of an accident happening with its severity, we ought to start this title by considering first major commercial nuclear accidents of level 7 on the INES scale, as a priority in analysis, so we must consider 1986 Chernobyl catastrophe where “Emissions from Chernobyl reactor exceeded a hundredfold the radioactive contamination of the bombs dropped on Hiroshima and Nagasaki”(10).
The latest New York Academy report on Chernobyl catastrophe has published horrendous facts of more than a million causalities; the new book concludes: Chernobyl death toll: 985,000, mostly from cancer (11). A paper by Kristina Voigt and Hagen Scherb also showed that after 1986, in the aftermath of Chernobyl, around 800,000 fewer children were born in Europe than one might have expected. The overall number of “missing” children after Chernobyl could have reached about one million (12); not to mention that the researchers have not covered all countries in their count!
According to UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation), adding to the latter casualties, between 12,000 and 83,000 children who lived in the vicinity of Chernobyl were born with congenital deformations, and also estimate that around 30,000 to 207,000 genetically damaged children were born worldwide (13). Amongst the interesting findings was that only 10% of the overall expected damage was actually seen in the first generation; the worse is yet to come with the offspring. A similar research on butterflies around Fukushima has yielded a similar result which will be discussed later.
As for the level 6 on the INES scale, it is classified as a serious nuclear accident that includes the accident at the Kyshtym facility in Russia in 1957, unfortunately not much research was published! on level 5, accidents with wider consequences include United Kingdom Windscale facility in the year 1957, Chalk River – Canada in 1952 and the Three Mile Island accident in 1979, after which the USA only licensed few new reactors; At present, only three nuclear reactors are being constructed in the United States: Watts Bar 2 reactor (1180 MW) which started decades ago, and was put on hold till 2007, expected by the IAEA to commercially operate in 2015. Another two reactors; vogtle 3 and Summer 2 of 1200 MW each, are expected to operate in 2017(14).
The Fukushima-Daitii nuclear accident in Japan on March 2011 is also classified as level 5. However, nuclear accidents of level 4 with local consequences include a long list, so are levels 4,3,2 and 1; a non-ending list of accidents(15).
In one year only (2008), according to an IRSN report, 205 accidents were recorded in nuclear facilities (safety and environmental), a noticeable 56% increase compared to the accidents recorded in 2005 which accounted for 131 accidents only. A typical example of those accidents is the leakage of 20 m3 of radioactive water from Socatri facility at Tricastin – France. Some of the radioactive water followed rain water drainage into the eco-system while the rest radioactive water seeped underground polluting the soil and under-ground water aquifers (16).
Since March 2011 funds of hundreds of billions of dollars are being allocated by TEPCO, the Tokyo Electricity Company, as to cover for the direct damages of the Fukushima disaster; however, the scale of damage on biodiversity and genetic disorders is not clearly understood.
The early mutations of butterflies around Fukushima are alarming as the mutations disorders have been increasing with the offspring. Mutations caused by Fukushima disaster radiation had affected 12% of adult pale grass blue butterflies in the surrounding area two months after the March 2011 disaster. When that batch mated, it produced an offspring with an 18% mutation rate. In the following generation, mutations were found in 34% of the butterflies born. In September 2011, a new study disclosed that the adult butterflies displayed 28% mutation rate and their offspring had a whopping 58% mutation rate (17).
In a similar study on mice after 25 years of the Chernobyl catastrophe, it yielded the following outcome: “The rate of mutation amongst the field mice is one hundred thousand times higher than normal” (18).
Another environmental damage connected with the nuclear industry is thermal pollution which is basically the form of water pollution that refers to degradation of water quality by any process that changes ambient water temperature. The main cause of thermal pollution is attributed to one particular industry, or to be more precise to nuclear power plants that use water as a coolant. After this water has been used as a coolant it is returned to the natural environment at a higher temperature. This change in water temperature decreases the amount of oxygen in the water which can lead to negative ecological effects.
Less oxygen in the water can harm fish population, as it can increase the metabolic rate of fish population and other aquatic animals so that they would more likely eat a lot more food in a shorter period of time than if their environment was not changed. This change can lead to imbalance in the food chain, thus resulting in significant long-term damage to many aquatic ecosystems.
Warmer water temperatures are known to lead to reproduction problems for many aquatic animals, and can further cause huge bacteria and plant growth. Warmer waters can even lead to algae bloom resulting in a consequent loss of more oxygen in the water. However, this damage is likely to be ethically benign compared to the mutations that result from radioactivity.
As for the effects of radioactivity on humans, scientists from the universities of Moscow and Leicester examined blood samples from 79 families, the parents of who had been living within a 300 km radius of nuclear reactors. The scientists were surprised by children born between February and September 1994 as cases of mutations had doubled (19). Peter karamoskos, a nuclear radiologist, quotes the following: “There is a linear dose-response relationship between exposure to ionizing radiation and the development of solid cancers in humans. It is unlikely that there is a threshold below which cancers are not induced”(20). Radiation can cause the breakdown in chromosomes, causing Down’s syndrome in babies as well as mental and physical disorders. Children exposed to radiation have a higher risk to develop leukemia (21).
Higher incidence of leukemia in UK children has been reported in the environment of the Sellafield (Windscale) fuel reprocessing facility in England (22-23), not far from the Dounreay reprocessing plant in Scotland (24-25), and also in similar children who lived within a few kilometers from the Aldermaston or Burghfield military weapons facilities in England (26). In a comprehensive survey done by Forman et al(27) and Cook-Mozaffari et al (28-29) reported excess mortality rate due to leukemia and Hodgkin’s disease particularly in young persons living in the vicinity of fourteen nuclear facilities, eight of them electricity generating nuclear plants.
In the United Kingdom, studies of populations living near nuclear power plants have yielded mixed results. Ewings et al (30) found increased incidence of leukemia and lymphoma in young persons near the Hinckley Point power station. Clap et al (31) reported an excess incidence of leukemia in men in five towns near the Pilgrim nuclear power station in Massachusetts.
Free Julian Assange, before it’s too late. Sign to STOP the USA Extradition
Make a submission about the radioactive waste dump!
The Federal Government wants to put a National Radioactive Waste Facility in Kimba or the Flinders Ranges in South Australia. The Department is calling for submissions and says these will be “one of the factors the Minister for Resources and Northern Australia may take into account when determining broad community support for the Facility.” If you live outside the ballot area, a submission is the only way to have your say! It only takes a minute to voice your opposition – use our online proforma submission and add whatever comments you like.
Submissions can be made by: Email: radioactivewaste@industry.gov.au Post: The Department of Industry, Innovation and Science. National Radioactive Waste Section. GPO Box 2013, Canberra ACT 2601| More information
FEDERAL. Inquiry into the prerequisites for nuclear energy in Australia Read the published submissions on the Parliamentary website. Read the SUMMARIES of submissions here.
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